We have seen consistent performances from these players on a week-to-week basis early in their careers, but the question with all of them is whether they can sustain this early performance and be consistent on a year-to-year basis.

So what's the cutoff to be regarded as the future at your position? I set the mark at 25 years old with more than three years in the league.

Any older than that with more experience, and chances are you're probably considered among the "present" and not the future. Also, any player who has been voted to a Pro Bowl is already regarded as one of the best at their position, and therefore is not included in this list (although I'm including Pro Bowl alternates here).

Beyond those requirements, these are the players that we'll be talking about as one of the best at their positions for years to come.

Quarterback: Colin Kaepernick, San Francisco 49ers

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We rarely expect much of a backup quarterback, but we would probably have laughed at the notion that a backup could actually improve a team that looked poised for a Super Bowl run—that is, before quarterback Colin Kaepernick did just that for the San Francisco 49ers.

Over the past two years alone, we have seen an influx of talent at quarterback unlike any other in recent memory, and with that, we have also witnessed a changing of the guard. The new breed of quarterback has an arm like The Hulk and legs like The Flash.

With 415 yards and five touchdowns on 63 carries (6.6 yards per attempt) as a runner, Kaepernick's stat line reads more like an explosive backup running back. That being said, with a 62.4 completion percentage, 8.3 yards per attempt and a 98.3 passer rating, his efficiency numbers as a passer read like any of your standard pocket passers.

Running Back: C.J. Spiller, Buffalo Bills

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There is perhaps no better big-play threat in the backfield than Spiller. According to stats website Pro Football Focus (subscription required), he earned a whopping 39.9 percent of his yards on 16 "breakaway" runs of 15 yards or more, the third-highest percentage in the NFL.

He does much of the work without the help of his blockers, having earned the best elusive rating in 2012, totaling 66 missed tackles and averaging 3.58 yards after contact (second-highest in the NFL).

Spiller is talented beyond just a runner, though. He adds great value in the passing game, where he caught 49 passes and averaged a gaudy 10.7 yards per reception, which ranked third among all running backs with at least 100 carries in 2012.

Spiller is already becoming a household name, but if he can build on his success from the 2012 season and carry a heavier workload for the Bills offense, he'll cement himself as one of the elite backs in the NFL.

Wide Receiver: Demaryius Thomas, Denver Broncos

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You could say Demaryius Thomas exploded onto the scene when he showed his burst through the Steelers defense in the 2012 playoffs, but his real emergence came in his third season under the guidance of Peyton Manning. Thomas finished in the top 10 in every receiving category except yards per reception, where he finished 15th.

In fact, Thomas was one of the selling points pitched by Broncos general manager John Elway when originally courting Manning (via ESPN):

My big selling point was those two receivers. ...[Manning] didn't know how good they were. I said, 'They're both 6-3, 225. One [Thomas] runs a 4.4 and the other runs a 4.5 40. And they're both young [25]. I sold him. I think those two guys get underplayed in all this.

Thomas' dominant performance in 2012 put him on the map, and his combination of size and speed—traits which Manning has remarked upon since day one—along with one of the most accurate quarterbacks in NFL history could lead to him being one of the top receivers in the NFL going forward.

Tight End: Kyle Rudolph, Minnesota Vikings

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Modern-day tight ends are more like big receivers, but there is still a lot of value in having a player who can contribute both as a receiver and a blocker.

At 6'6" and 260 pounds, Kyle Rudolph has size comparable to Patriots tight end Rob Gronkowski and is used in a similar way in the Vikings offense. He tied for third with eight red-zone receiving touchdowns in 2012 and caught 80 percent of passes thrown his direction in the red zone, the highest for any tight end with over 10 red-zone targets.

Still, Rudolph has shone like a red-nosed reindeer even in games where he has been absent from the stat sheet. Vikings head coach Leslie Frazier remarked after a loss to the Seattle Seahawks that Rudolph did a "great job in blocking, which really set up some of those nice runs that [running back] Adrian [Peterson] had." (Peterson rushed 17 times for 182 yards, 10.7 yards per carry and two touchdowns against the league's No. 10 run defense.)

Questions continue to surround the development of quarterback Christian Ponder, but a tight end is always a young quarterback's best friend. Rudolph could be the best friend Ponder could ever ask for.

Offensive Tackle: Nate Solder, New England Patriots

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With exotic blitz packages coming at all directions, the distinction between a left tackle and a right tackle is no longer as clear cut as getting a pass-blocker for the left side and a run-blocker for the right side.

Nate Solder has showed the ability to play on both sides already in his two-year career, having filled in at right tackle for the majority of the 2011 season and then moving to the left side after left tackle Matt Light retired.

Solder's size is what sets him apart; at 6'8" and 320 pounds, he has the length to reroute agile pass-rushers around the quarterback, which also allows him to prevent hard-charging bull-rushers to get in his pads. Even when they do, he still has the size to hold his ground at the point of attack. As a former tight end, Solder also has rare agility to keep up with edge-rushers.

There is some work to be done for Solder in the passing game—29 hurries and 41 total pressures is simply too much in a spread attack—but all the tools are there. Solder's size and skill set make him part of a new age of offensive tackle in the NFL.

Offensive Guard: Kevin Zeitler, Cincinnati Bengals

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The foundation for a good passing game is a clean pocket, and for a quarterback to step into his throws, the middle of the line is especially important.

Kevin Zeitler was considered one of the NFL's best pass-blocking guards all season long by Pro Football Focus (subscription required), who rated him the fourth-most efficient pass-blocking guard in the NFL (15 total pressures in 2012). He gave up one or no pressures in 14 of 17 total games.

His abilities in pass protection will go a long way toward his future in the NFL, but what about in the running game? That was the only knock on him from Bleacher Report's Matt Miller in ranking Zeitler as the 10th-best guard in the NFL:

Zeitler struggled a bit in the run game, especially early in the year as he adjusted to angles and technique at the NFL level. The natural ability is there, and we started to see later in the year the technique needed to dominate. Hand placement is key for Zeitler, as he must control defenders better and not allow them to get off blocks to make plays.

Those are all coachable flaws, and we saw his raw abilities as a run-blocker throughout his career in Wisconsin. As those skills translate to the NFL with experience, Zeitler could grow into one of the best guards in the league.

Center: Mike Pouncey, Miami Dolphins

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The job of an NFL center is already difficult enough—from getting all the protection calls right, to making sure everyone is working together, to blocking some of the biggest players on the defensive line right up the middle.

Somehow, Mike Pouncey finds time in his busy schedule to fit in duties that are often reserved for a guard, pulling as a lead blocker on outside runs and screens.

In fact, he graded out as the fifth-best screen-blocking center in the NFL, according to Pro Football Focus (subscription required). He also ranked second in their pass-blocking efficiency metric, allowing just seven total pressures and two sacks on his quarterbacks.

There have been a lot of great centers in the NFL, but very few have carried the promise of innovation at the position. That's what makes Pouncey the future at this position.

4-3 Defensive End: Greg Hardy, Carolina Panthers

Jake Roth-USA TODAY SportsGreg Hardy will feast on the NFL for years to come.

The Panthers have slowly built their defense into a solid unit, and one of the keys to that ascension was the improvement of Greg Hardy.

He started off slow with just seven combined sacks in his first two seasons in the league, but he jumped into high gear in 2012 with 11 sacks (four of which were assisted).

Hardy ranked fifth among 4-3 defensive ends in Pro Football Focus' pass-rushing productivity, logging 59 total pressures (subscription required). He was no slouch against the run either, and logged 14 tackles for loss, which tied him for fifth in the NFL among all defensive ends.

The job description for a 4-3 defensive end is not tough to wrap your head around: set the edge against the run, rush the passer, contain the pocket when necessary. Hardy has shown he can do all three, and in an emerging Panthers defense, he could be a household name in no time.

4-3 Defensive Tackle: Nick Fairley, Detroit Lions

that Nick Fairley doesn't get the attention he deserves because Ndamukong Suh is too busy stomping people and throwing them head-first into the turf.

Fairley was outright dominant last season, especially in the second half of the year.

He was one of the best pass-rushing defensive tackles in the NFL, with 34 combined pressures (21 hurries, eight hits, five sacks). He wasn't just a pass-rusher, though; according to Advanced NFL Stats, his 10 tackles for loss were the fourth-most for any defensive tackle in the NFL last year.

He needs to work on some elements of discipline, drawing too many flags (11 on the season), many of which came for being offsides. With some refinement there, he could be one of the best at his position without question. If he continues to play like he did in 2012, though, he'll make a huge impact for the Lions regardless.

3-4 Defensive End: Muhammad Wilkerson, New York Jets

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There is little doubt that Muhammad Wilkerson would have received much more media attention if Houston Texans defensive end J.J. Watt hadn't been dominating the headlines. Wilkerson is just behind him in terms of the best 3-4 defensive ends the AFC has to offer.

Not only did Wilkerson rank third among 3-4 defensive ends in run stopping (10.1 percent of his tackles counted as an offensive failure in a given situation), but he was also one of the most productive pass-rushing 3-4 defensive ends (37 total pressures was seventh-most at the position).

The potential for greatness has his coaches geeked up to see what he brings to the table in 2013.

I've had my popcorn in the microwave since December, when Wilkerson was snubbed from the Pro Bowl, but no matter—that baffling instance allowed me to put him on this list, right where he belongs as the future of 3-4 defensive ends in the NFL.

The size of 3-4 nose tackles is often a point of humor for some, but Williams began taking his size and conditioning seriously last offseason, and it showed. With a run stop percentage of 8.6, he ranked sixth among qualifying defensive tackles.

He will never be among the league's elite pass-rushing defensive tackles, but that's not his job. As long as he continues to hold the point of attack and soak up blockers for the linebackers to make plays in space behind him, he'll be a very effective 3-4 nose tackle.

4-3 Outside Linebacker: Lavonte David, Tampa Bay Buccaneers

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A 4-3 outside linebacker is supposed to be a jack of all trades, with the range to make plays in space and the strength to hold the point of attack as well as the ability to bring some pressure on the blitz.

Lavonte David did a little bit of everything as a rookie for the Buccaneers. His 19 combined pressures were the sixth-most for any 4-3 outside linebacker last year.

Also, chew on this: David's 20 tackles for loss were the second-most by any rookie since 2000, edging out stud defensive end Dwight Freeney, outside linebackers Von Miller and Clay Matthews and legendary linebacker Brian Urlacher.

He has some work to do in coverage; although his 0.94 yards per cover snap put him in the top 10 at his position, he allowed completions on 79.2 percent of throws into his coverage and gave up five touchdowns.

That being said, he showed all the necessary athletic ability to be a top linebacker for years to come.

3-4 Outside Linebacker: Justin Houston, Kansas City Chiefs

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Oftentimes, a 3-4 outside linebacker can be a de facto 4-3 defensive end. Many of the top 3-4 outside linebackers are hardly ever asked to drop into coverage, and others struggle to set the edge against the run.

Justin Houston has the versatility to do it all and is utilized for all of those skills.

He missed just two tackles in the running game and just one in the passing game, making him the fifth-most efficient tackling 3-4 outside linebacker in the league last year.

He dropped into coverage more frequently than 49ers linebacker Aldon Smith, Green Bay Packers linebacker Clay Matthews and other stud pass-rushers. He earned the fourth-highest coverage grade of any 3-4 outside linebacker according to Pro Football Focus (subscription required).

That being said, he doesn't lack any talent as a pass-rusher, having ranked sixth among 3-4 OLBs in PFF's pass-rushing productivity with 44 total pressures (27 hurries, seven hits, 10 sacks).

Houston has a full compliment of skills and looks primed to put them all to use on his way to the top of the rankings at his position.

Inside Linebacker: Luke Kuechly, Carolina Panthers

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There's no quicker way to cement your status as the future of your position than to win the Rookie of the Year award, and Luke Kuechly's 2012 season was good enough to earn him that honor on the defensive side of the ball.

The Panthers defense was much maligned in 2011, ranking 27th in points and 28th in yards. Kuechly came in and quickly changed the culture, as the unit leaped nine spots in the points standings and 18 spots in the yardage standings.

Kuechly spent the season going sideline-to-sideline, leading the league with 164 total tackles and becoming the first rookie to lead the league in that category since 49ers linebacker Patrick Willis back in 2007. In fact, 13.4 percent of his tackles in the running game were considered run stops, which ranked him third in that metric according to Pro Football Focus (subscription required).

He showed great awareness in recovering three fumbles, but also showed solid ball skills in the passing game with eight pass breakups and two interceptions. He still has some work to do in that area after allowing a reception on every 9.5 snaps in coverage (26th out of 32 qualifying linebackers), but he has clearly laid the foundation for a great career.

Cornerback: Casey Hayward, Green Bay Packers

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The transition from Charles Woodson to Casey Hayward promises to be a smooth one for the Packers.

The rookie cornerback had an astounding season by any measure. His six interceptions tied for fifth-most in the league, and according to Pro Football Focus, he gave up a passer rating of just 31.1 into his coverage—the lowest for any cornerback in the NFL (subscription required).

Much like Woodson, Hayward was seen in the slot on a good portion of his snaps (338 out of 501 coverage snaps), which may be a result of his talents against the run, where he logged nine run stops and didn't miss a tackle according to PFF.

Hayward is not the prototype perimeter shutdown corner on the outside, but he has all the skills to contribute heavily in a league where the nickel defense is the new base defense.

Free Safety: Devin McCourty, New England Patriots

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Devin McCourty was voted to the Pro Bowl as a rookie and should therefore be left off the list, but he got in as a cornerback.

He had a tough 2011 season, but moved to safety at the tail end of the season and was supposed to stay there. However, he was moved back to corner due to injuries and poor play. McCourty has yet to play a full season at free safety, but in 2012, he showed the potential to be one of the best in the league at the position.

His range allowed the Patriots to run Cover 2 on the back end, which they had been trying (unsuccessfully) to do all season long. Only at that point did it finally begin to work, as the Patriots shored up their problems defending the deep pass.

According to Pro Football Focus (subscription required), McCourty allowed a passer rating of just 10.1 on throws into his coverage, the best of any safety last season.

McCourty's ball-hawking skills are perfect for the safety position. He was always at his best with his eyes reading the quarterback, and now, he gets to do that on every play he's in pass coverage. That's bad news for opposing quarterbacks looking to go deep against the Patriots defense in 2013 and beyond.

Strong Safety: Reshad Jones, Miami Dolphins

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These days, it's no longer acceptable for a strong safety to be strictly an "in the box" defender. With teams running a heavy amount of Cover 2 on the back end, strong safeties need to have the sideline-to-sideline range to make plays all over the field.

That's not all. With receiving tight ends becoming more and more in vogue with each passing year, strong safeties are also being asked to line up against them in man coverage. On top of all that, they're still asked to carry out many of the same duties asked of those typical in-the-box safeties.

Reshad Jones checks off all three of those boxes with ease. He made plays all over the field in both the running and passing game for the Dolphins, and he was fourth on the team with 94 total tackles in 2012. He was also first with four interceptions.

According to Pro Football Focus (subscription required), Jones allowed a passer rating of 38 on throws into his coverage, with 48.7 percent completions and just one touchdown allowed.

Kicker: Blair Walsh, Minnesota Vikings

The Minnesota Vikings tied for 19th in the NFL in total touchdowns (39) and yet ranked 14th in points (379). That's no mistake; that's the power of Blair Walsh.

Yes, Walsh is a Pro Bowler and an All-Pro, but his feats as a rookie were remarkable enough that he should be exempt from our previous guidelines.

Walsh ranked fourth in accuracy percentage while going 10-for-10 from 50 yards or more. Granted, nine of those kicks were in a dome, but he took the second-most such attempts in the league and made the most 50-yard field goals of anyone in the NFL last year.

His combination of power and accuracy should make him the envy of special teams coordinators across the league.

Punter: Bryan Anger, Jacksonville Jaguars

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The Jaguars may never be justified for spending a third-round pick on a punter, but Bryan Anger has undeniable talent.

Anger's rookie season was prolific. He set NFL rookie records for gross average (47.8 yards per punt) and net average (40.8) in 2012 while also setting franchise records in both categories. Beyond that, he ranked sixth in punts landing inside the 20 (31).

While his career got off to a rough start as a dubious draft choice, his strong leg and accuracy could go a long way in changing what people think about Anger.